Singapore Airlines flight SQ-12 had to return and make an emergency landing at Narita International Airport, Japan, on September 15.
The Airbus A380-800 plane was turned back after the crew had to shut down one of the engines due to vibrations. The flight was en-route to Los Angeles, California at the time.
The plane landed uneventfully
The airline arranged a replacement plane for the passengers.

American Airlines flight AA-759 encountered turbulence near Long Island, New York, on August 5th.
American Airlines flight AA-5474 had to return and make an emergency landing in Charlotte, North Carolina, on October 4th.